1. Field of the Invention
The present invention relates to a brushless motor using permanent magnets and electromagnetic coils.
2. Description of the Related Art
One proposed structure of the brushless motor using the permanent magnets and the electromagnetic coils is disclosed in, for example, Japanese Patent Laid-Open No. 2001-298982.
In the electric motor of the prior art structure, a rotor rotates in a stator, and the rotational motion of the rotor is transmitted to a rotating shaft by fixation of the rotor to the rotating shaft. The rotational motion of the rotating shaft is then transmitted to a driven member, such as a wheel, via a gear or another equivalent transmission mechanism or direct coupling of the rotating shaft with the driven member. In this conventional structure, however, a torsion occurring on the rotating shaft undesirably causes delayed transmission of the rotational motion of the rotor to the wheel or another driven member and requires high torsion strength of the rotating shaft for transmission of a large rotational force. These problems are not limited to the motors but are also found in generators. In the motor of this prior art structure, only one rotating shaft is directly rotatable by one motor, so that the driven member is linked with the one rotating shaft.